Induction of nitric oxide synthase by lipopolysaccharide and its inhibition by auranofin in RAW 264.7 cells.
In RAW 264.7 cells, a murine macrophage cell line, treatment with lipopolysaccharide (1 to 10 ng/ml) stimulated production of nitric oxide (NO), which was inhibited by L-N(G)-monomethyl-L-arginine acetate, an inhibitor of NO synthase. Auranofin, an orally active chrysotherapeutic agent, also inhibited the lipopolysaccharide-induced NO production in a concentration-dependent manner (0.3 to 3 microM). Other gold salts such as aurothioglucose and aurothiomalate had no effect. Western blot analysis demonstrated that the lipopolysaccharide (10 ng/ml)-induced expression of inducible NO synthase protein was inhibited by auranofin as well as by the protein synthesis inhibitor cycloheximide. In addition, the lipopolysaccharide-induced increase in the level of mRNA for inducible NO synthase was also lowered by auranofin. Furthermore, auranofin showed no direct effect on the conversion of [3H]arginine to [3H]citrulline by the cell lysate. These findings indicate that auranofin inhibits lipopolysaccharide-induced NO production by suppressing the expression of inducible NO synthase.
Yamashita
M
M
Department of Pathophysiological Biochemistry, Faculty of Pharmaceutical Sciences, Tohoku University, Aoba Aramaki, Sendai, Miyagi, Japan.
Niki
H
H
Yamada
M
M
Mue
S
S
Ohuchi
K
K
D000818:Animals; D018501:Antirheumatic Agents / Q000494:pharmacology*; D001310:Auranofin / Q000494:pharmacology*; D015153:Blotting, Western; D002460:Cell Line; D002474:Cell-Free System; D004731:Endotoxins / Q000037:antagonists & inhibitors* / Q000494:pharmacology*; D004790:Enzyme Induction / Q000187:drug effects; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000201:enzymology*; D051379:Mice; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000378:metabolism; D016133:Polymerase Chain Reaction; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis
D018501:Antirheumatic Agents; D004731:Endotoxins; D004791:Enzyme Inhibitors; D009573:Nitrites; D012333:RNA, Messenger; D001310:Auranofin; C044101:endotoxin, Escherichia coli; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse